Handling local notifications when the user presses the icon instead of the alert

问题

Here is the situation that I want to handle quoted from Apple's documentation.

As a result of the presented notification, the user taps the action button of the alert or taps (or clicks) the application icon. If the action button is tapped (on a device running iOS), the system launches the application and the application calls its delegate’s application:didFinishLaunchingWithOptions: method (if implemented); it passes in the notification payload (for remote notifications) or the local-notification object (for local notifications).

If the application icon is tapped on a device running iOS, the application calls the same method, but furnishes no information about the notification . If the application icon is clicked on a computer running OS X, the application calls the delegate’s applicationDidFinishLaunching: method in which the delegate can obtain the remote-notification payload.

How do I handle this situation if there is no information about the notification?

回答1:

If I understand you correctly, it sounds like you have a UILocalNotification that has been fired, but you need to still handle it if the user taps the application icon instead of the notification. Correct?

If this is the case, then to my knowledge you won't be able to handle the notification from the app delegate, because the app is not being launched or brought out of the background by the notification, but instead by the user's interaction.

However, if you are setting a badgeNumber on the application with the notification then you could try something like this:

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
if (launchOptions[UIApplicationLaunchOptionsLocalNotificationKey]) {
    UILocalNotification *notification = launchOptions[UIApplicationLaunchOptionsLocalNotificationKey];
} else if ([UIApplication sharedApplication].applicationIconBadgeNumber > 0) {
    // Assume that user launched the app from the icon with a notification present.
}}

You may also have to check the badgeNumber in - (void)applicationDidBecomeActive:(UIApplication *)application as well.

回答2:

Improve to @Aron Crittendon answer:

Consider also to handle that in applicationDidBecomeActive:

-(void)applicationDidBecomeActive:(UIApplication *)application
{
    if ([UIApplication sharedApplication].applicationIconBadgeNumber > 0) {
        //application is in background, fired notification and user tapped app icon with badge
    }
}

回答3:

As the documentation states, if you tap the icon on iOS (and not the notification's alert/banner) then the same method is called but you get no notification information. There is no way to handle a local notification simply by tapping the app icon.

来源：https://stackoverflow.com/questions/24540304/handling-local-notifications-when-the-user-presses-the-icon-instead-of-the-alert